Many symbioses have evolved between vascular plants and soil microorganisms which result in plants having an improved acquisition of mineral nutrients, improved growth and survival. Of these symbioses, the arbuscular endomycorrhizal fungi are certainly the most ubiquitous.
Arbuscular endomycorrhizal fungi were thought to be solely of vesicular type and were referred to as "VAM fungi". Although, the expression "VAM fungi" is still used it is no longer intended to be restricted to vesicular arbuscular endomycorrhizal fungi, since arbuscular endomycorrhizal fungi are known that do not form vesicles.
A better knowledge of these symbiotic organisms might have important economic benefits since they can associate with many important crop plants. Unfortunately, these fungi have never been successfully grown in culture and hence, all the fungi must be maintained as co-cultures on colonized roots. Furthermore, it is time consuming and often not feasible to only recognize, identify and quantify the arbuscular endomycorrhizal fungi in colonized roots.
It would be highly desirable to have means to rapidly detect, identify and possibly quantify the arbuscular endomycorrhizal fungi.
DNA probes have become a widely-employed technique for detecting various organisms present in low amounts in complex samples. Thus, it would be desirable to have a DNA probe specific for the detection of the arbuscular endomycorrhizal fungi.